Search PubMed⌕ Search

Biomedical subjects

R C Harvey

Publications and source records attributed to R C Harvey.

At least 37 records · Page 2Linked to original sources

Characterization of a candidate bcl-1 gene.

The t(11;14)(q13;q32) translocation has been associated with human B-lymphocytic malignancy. Several examples of this translocation have been cloned, documenting that this abnormality joins the immunoglobulin heavy-chain gene to the bcl-1 locus on chromosome 11. However, the identification of the bcl-1 gene, a putative dominant oncogene, has been elusive. In this work, we have isolated genomic clones covering 120 kb of the bcl-1 locus. Probes from the region of an HpaII-tiny-fragment island identified a candidate bcl-1 gene. cDNAs representing the bcl-1 mRNA were cloned from three cell lines, two with the translocation. The deduced amino acid sequence from these clones showed bcl-1 to be a member of the cyclin gene family. In addition, our analysis of expression of bcl-1 in an extensive panel of human cell lines showed it to be widely expressed except in lymphoid or myeloid lineages. This observation may provide a molecular basis for distinct modes of cell cycle control in different mammalian tissues. Activation of the bcl-1 gene may be oncogenic by directly altering progression through the cell cycle.

Amino Acid Sequence↗

The effect of air abrasive polishing on blood pH and electrolyte concentrations in healthy mongrel dogs.

The recent re-emergence of air abrasive polishing as an adjunct to professional tooth cleaning has been accompanied by a substantial amount of research. Most of this research has focused on the efficacy of the Prophy-Jet and similar devices in the removal of plaque and stain and on the effects of such devices on restorative materials and the various hard structures of the tooth. Little attention has been paid to the effects of mucosal absorption of the sodium bicarbonate in the polishing abrasive. The purpose of this study was to measure any changes in arterial blood chemistry resulting from the use of the Prophy-Jet. The values for pH, sodium, and bicarbonate, as well as other electrolytes, were measured in 10 dogs over a 2 hour period following a 5 minute timed use of the Prophy-Jet. Of all the parameters examined, only the potassium concentration showed a statistically significant change, and the magnitude of this change was not felt to be clinically significant. The pH and concentrations of sodium and bicarbonate remained essentially unchanged with the use of the Prophy-Jet.

Air↗

Critical care surgical techniques.

A veterinarian dealing with critical and trauma patients must be proficient with techniques for tracheostomy, thoracostomy tube placement for chest drainage, diagnostic peritoneal lavage, and autotransfusion. The utilization of these techniques may be life-saving in the critical patient. A tracheostomy is indicated in any patient with upper airway obstruction that cannot be managed with supplemental oxygen and/or orotracheal intubation. A tracheostomy tube with an inner cannula is preferred. Tracheostomy tubes should be cleaned at 3- to 4-h intervals, and methods should be employed to decrease thick tracheal secretions and to remove them from the trachea. A patient with a tracheostomy tube should be monitored continuously. A thoracostomy tube is indicated in any patient with large and/or continuous accumulation of air, blood, fluid, or chyle in the pleural space. The thoracostomy tube should be at least the same size as the patient's main stem bronchus. The thoracostomy tube is placed aseptically at the seventh intercostal space at the junction of the upper one third and lower two thirds of the lateral chest wall. Fluid or air may be removed from the chest intermittently with a three-way stopcock attached to the thoracostomy tube and a 60-ml syringe. If continuous drainage is needed, a continuous underwater seal and suction system should be used. Diagnostic abdominal paracentesis and peritoneal lavage are useful techniques in the determination of abdominal trauma, hollow viscus rupture, peritonitis, hepatic trauma, and urinary system trauma. When a multiholed catheter and lavage are used, the accuracy of detecting abdominal trauma is 95 per cent. When only needle paracentesis is used, the accuracy drops to 47 per cent. Abdominal lavage fluid can be analyzed for bacteria, whole blood, white blood cells, free bilirubin, creatinine, blood urea nitrogen, amylase, alkaline phosphatase, and alanine aminotransferase. Large volumes of whole blood recovered from abdominal or thoracic paracentesis can be reinfused into the patient if needed, providing it is not contaminated or markedly hemolyzed. The blood should be collected aseptically into blood bottles or bags. If the bleeding is ongoing or the blood only a few hours old, anticoagulants should be used. If the hemorrhage is several hours old, then clotting and defibrination has already occurred and the blood can be collected into "dry" bags or bottles. Before use, abdominal blood should be analyzed for urine, bile or fecal contamination. Blood collected from the thoracic cavity is much less likely to be contaminated. Autotransfused blood is administered through a standard blood administration set.

Animals↗

Translocations and rearrangements in T-cell acute leukemias with the t(11;14) (p13;q11) chromosomal translocations.

Chromosomal translocations involving the T-cell receptor alpha and delta genes at q11 on chromosome 14 are the most common cytogenetic abnormalities in patients with T-cell tumors. We have demonstrated that the t(11;14)(p13;q11) translocation in two T-ALL patients involves the J delta region suggesting that the translocation proceeds or coincides with delta gene rearrangement. Additional rearrangements on both normal and translocated chromosomes 14 are described including rearrangement of both Tcr-alpha and Tcr-delta genes, and deletions within the J alpha region. The polyclonality of rearrangements on the normal chromosome 14 in one of the patient samples demonstrates that T-cell receptor rearrangement continues after the translocation event. The identification of clonally expanded rearrangements involving both the Tcr-delta and the Tcr-alpha genes in a single patient suggests a cascade model for delta----alpha expression may be a viable pathway for T-cell maturation.

Base Sequence↗

Anesthetic and supportive management during experimental pulsatile flow perfusion studies in calves.

The purpose of this study was to determine the factors influencing successful experimental cardiopulmonary bypass studies using pulsatile flow perfusion and the medications and methodology necessary to produce successful bypass in calves. In six calves showing no cardiopulmonary pathology prior to bypass procedures, successful anesthesia and surgical intervention was accomplished. Animals were maintained on 5 hours of pulsatile flow bypass perfusion. Successful recovery from the procedures was accomplished. In two calves with pre-existing pulmonary pathology, anesthetic and surgical intervention was accomplished with the utilization of extensive anesthetic management and cardiac supportive medications until the animals could be initiated into 5 hours of pulsatile flow bypass perfusion, in spite of major pulmonary dysfunction. In these two animals, attempts to resuscitate upon termination of pulsatile flow perfusion were unsuccessful due to pre-existing excessive lesions in the lungs. This study shows a contrast between complete success of a pulsatile flow system in normal subjects versus the ultimate failure in experimental animals with pre-existing pulmonary pathology. The inability of experimental calves with a diseased lung to resume spontaneous cardiopulmonary function after the challenges of thoracic intervention indicates the unsuitability of animals with marked pre-existing pulmonary disease status for use in cardiopulmonary bypass studies.

Anesthesia, General↗

A common mechanism of chromosomal translocation in T- and B-cell neoplasia.

The chromosomal breakpoint involved in the t(8;14)(q24;q11) chromosome translocation in the SKW-3 cell line, which directly involves the 3' flanking region of the c-myc gene, was cloned and sequenced. The breakpoint on chromosome 8 mapped to a position 3 kb 3' of c-myc while the chromosome 14 breakpoint occurred 36 kb 5' of the gene for the constant region of the alpha chain of the T-cell receptor (TCR). The translocation resulted in a precise rearrangement of sequences on chromosome 8 and what appears to be a functional J alpha segment on chromosome 14. Signal sequences for V-J joining occurred at the breakpoint positions on both chromosomes 14 and 8, suggesting that the translocation occurs during TCR gene rearrangement and that it is catalyzed by the enzymatic systems involved in V-J joining reactions. The involvement of c-myc in the translocation and the association of joining signals at the breakpoints provides a parallel to the situation observed in the translocations involving c-myc and the immunoglobulin loci in B-cell neoplasms and suggests that common mechanisms of translocation and oncogene deregulation are involved in B- and T-cell malignancies.

B-Lymphocytes↗

A chronic sheep preparation for the study of drug pharmacokinetics in spinal and ventricular CSF.

We describe a sheep preparation utilizing chronic vascular and subarachnoid catheterization and ventriculocisternal perfusion. This preparation allows simultaneous, atraumatic sampling of plasma and CSF after drug administration by the intravenous, intracerebroventricular, or lumbar intrathecal (i.t.) routes in an unanesthesized animal. This sheep preparation provides a convenient means of studying the CSF distribution of exogenous and/or endogenous substances. During intravenous infusion at a rate of 2.2 micrograms/kg/min, morphine appears in cisternal CSF within 15 min. The steady-state plasma concentration and CSF flux (or appearance rate) of morphine was 0.037 and 0.009 micrograms/min, respectively. At steady state, 0.008% of the administered dose appears in CSF/min. The coadministration of morphine, methadone, and [14C]sucrose into the fifth lumbar subarachnoid space is associated with the simultaneous appearance of morphine and [14C]sucrose, but not methadone, in cisternal CSF. The ratio of [14C]sucrose to morphine increased by nearly sevenfold in cisternal CSF, indicating clearance of morphine relative to [14C]sucrose as the compounds ascend in the CSF axis. The simultaneous appearance of morphine and [14C]sucrose in cisternal CSF after lumbar subarachnoid administration indicates that morphine, like sucrose, is distributed within the CSF by bulk flow. This sheep preparation can be used to provide the quantitative data necessary for the development of pharmacokinetic-pharmacodynamic models that relate plasma and CSF concentrations of opiates to their pharmacological effects. These studies will help to provide the pharmacological rationale for the administration of opiates by novel routes for pain management in man.

Animals↗

Purification of plasminogen activator from Rous sarcoma virus-infected chick embryo fibroblast culture medium.

A new procedure for the purification of plasminogen activator secreted by cultured Rous sarcoma virus-infected chick embryo fibroblasts was described. The enzyme was isolated from culture medium containing 0.75% calf serum depleted of plasminogen by lysine-agarose affinity column chromatography and of high-molecular-weight protease inhibitors by ultracentrifugation. The culture conditions allowed convenient preparation of large amounts of culture fluid with relatively high concentrations of plasminogen activator. The purification of the enzyme was accomplished by affinity chromatography on fibrin-celite and p-aminobenzamidine-agarose columns, and by gel-filtration chromatography in the presence of urea. The activity was recovered in greater than 90% yield, and the enzyme was essentially homogeneous when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Yields from 500 ml culture fluid exceeded 500 micrograms.

Animals↗

Paralysis due to a glomangioma in a Macaca mulatta.

A glomangioma at the 6-7 thoracic intervertebral space caused compression of the spinal cord with posterior paralysis in an irradiated 20-year-old female rhesus monkey (Macaca mulatta). Glomangiomas are tumors of arterial-venous shunts, are rare and have only been reported in irradiated rhesus monkeys.

Animals↗

Anesthetic waste gases in veterinary medicine: analysis of the problem and suggested guidelines for reducing personnel exposures.

Anesthetic waste gases are a concern to veterinarians and their personnel. Investigations have shown that many of the anesthetic units used in veterinary medicine have leaks that contribute to operating room contamination. Many others do not have appropriate scavanging attachments to remove escaping gases. Personnel were frequently observed carelessly using equipment or handling anesthetic agents in a manner contributing to excessive exposure. Proper maintenance of equipment and careful use of gaseous anesthetic agents can significantly reduce waste gas levels and exposure of personnel.

Air Pollutants, Occupational↗

A technique for bioinstrumentation of the thorax of miniature swine.

A surgical technique for sternal thoracotomy was developed for use in miniature swine. An incision was made from the midpoint of the neck to the tip of the xiphoid cartilage. The thorax was entered by dividing the sternum along its long axis with an electric oscillating saw. The thoracotomy was closed with 3-mm wide polyester fiber umbilical tapes placed around each sternebrae to appose the cut surfaces. The technique provided good access to the cranial vena cava, both atria and appendages, both ventricles, great cardiac veins, coronary sinus, ascending aorta and arch, and the pulmonary artery. Miniature swine tolerated this procedure well. It appeared to be less painful than lateral approaches and produced fewer pleural adhesions because only the mediastinum was entered.

Animals↗

Mutagenesis at the ad-3A and ad-3B loci in haploid UV-sensitive strains of Neurospora crassa. V. Comparison of dose--response curves of single- and double-mutant strains with wild-type.

The interactions of mutant alleles that individually confer radiation sensitivity in Neurospora crassa are being studied with regard to their effects on radiation-induced inactivation and forward-mutation induction at the ad-3 loci. This paper reports attempts to construct 3 double-mutant strains containing the following pair-wise combinations of repair-deficient mutants: upr-1,uvs-2; uvs-2,uvs-6; and uvs-3,uvs-6. The double-mutant strain with the 2 excision-repair-deficient mutants upr-1 and uvs-2 shows increased sensitivity to X-ray-induced mutagenesis and inactivation, relative to that shown by either of the parental single-mutant strains. This double mutant is no more sensitive than the parental single-mutant strains to either UV mutagenesis or inactivation. The combination of the uvs-2 and uvs-6 double-mutant strain is considerably more sensitive to both UV and X-ray inactivation than either the uvs-2 or uvs-6 strain, but it shows no greater sensitivity than the parental strains to ad-3 mutation induction by either agent. The combination of the uvs-3 and uvs-6 alleles is inviable. Tetrad analysis and microscopical examination of ascospores shows that ascospores of presumptive genotype uvs-3, uvs-6 do not grow beyond the formation of a few hyphal threads. The lethal and mutagenic effects of UV and X-irradiation in these double-mutant strains are interpreted in terms of the repair systems in Neurospora and other microorganisms.

DNA Repair↗

Effects of chemical and physical mutagens on the frequency of a large genetic duplication in Salmonella typhimurium. I. Induction of duplications.

In Salmonella typhimurium a simple selection has been described to detect bacteria that are merodiploid for almost one-third of the chromosome. The selective procedure is based upon improved utilization of L-malate as the sole carbon source in merodiploid strains. The spontaneous frequency of the duplication in haploid strains is approximately 10(-4) per cell plated. Following the exposure of a haploid strain to mutagenic agents, there is a dose-dependent increase in the duplication frequency above the spontaneous level. In this paper we describe the induction of genetic duplications in Salmonella typhimurium by X-rays, ultraviolet light (UV), ethyl methanesulfonate (EMS), nitrous acid, and the azaacridine half mustard, ICR-372.

Acridines↗

Quantitative analysis of major, minor and trace elements in gallbladder bile of patients with and without gallstones.

The concentration of 25 major, minor and trace elements in human bile was determined by inductively coupled plasma atomic emission spectrometry. Gallbladder bile was obtained during surgery from patients with cholesterol gallstones, pigment stones and with no biliary tract abnormalities (controls). Comparison of the concentration of elements (microgram per gram of solids) did not reveal any significant differences among the three patient groups. The in vitro nucleation time was not related to the concentration of any element measured.

Bile↗

Isoflurane anesthesia for equine colic surgery. Comparison with halothane anesthesia.

Isoflurane was compared with halothane as an anesthetic agent for emergency colic surgery in a series of 38 juvenile and adult horses. After presurgical stabilization with fluids and supportive medications, anesthesia was induced by intravenous xylazine and/or diazepam followed by ketamine. Anesthesia was maintained with isoflurane or halothane in oxygen with controlled ventilation. Heart rates (HR), arterial blood gases, mean arterial pressures (MAP), rate pressure products (RPP), requirements for cardiovascular support medications, and recovery times to standing were compared using nonparametric methods. Cardiopulmonary responses to isoflurane and halothane anesthesia were generally comparable although some temporal differences were observed. Higher HR (p less than 0.02) and lower PaCO2 levels (p less than 0.01) were identified during the course of isoflurane anesthesia. Recovery times to standing were significantly shorter (0.02 less than p less than 0.05) after isoflurane than halothane anesthesia.

Anesthesia↗